1 files changed, 86 insertions, 0 deletions
diff --git a/m4/mkstemp.m4 b/m4/mkstemp.m4
new file mode 100644
index 0000000..28b7889
--- /dev/null
+++ b/m4/mkstemp.m4
@@ -0,0 +1,86 @@
+#serial 27
+
+# Copyright (C) 2001, 2003-2007, 2009-2020 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# On some hosts (e.g., HP-UX 10.20, SunOS 4.1.4, Solaris 2.5.1), mkstemp has a
+# silly limit that it can create no more than 26 files from a given template.
+# Other systems lack mkstemp altogether.
+# On OSF1/Tru64 V4.0F, the system-provided mkstemp function can create
+# only 32 files per process.
+# On some hosts, mkstemp creates files with mode 0666, which is a security
+# problem and a violation of POSIX 2008.
+# On systems like the above, arrange to use the replacement function.
+AC_DEFUN([gl_FUNC_MKSTEMP],
+[
+  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
+  AC_CHECK_FUNCS_ONCE([mkstemp])
+  if test $ac_cv_func_mkstemp = yes; then
+    AC_CACHE_CHECK([for working mkstemp],
+      [gl_cv_func_working_mkstemp],
+      [
+        mkdir conftest.mkstemp
+        AC_RUN_IFELSE(
+          [AC_LANG_PROGRAM(
+            [AC_INCLUDES_DEFAULT],
+            [[int result = 0;
+              int i;
+              off_t large = (off_t) 4294967295u;
+              if (large < 0)
+                large = 2147483647;
+              umask (0);
+              for (i = 0; i < 70; i++)
+                {
+                  char templ[] = "conftest.mkstemp/coXXXXXX";
+                  int (*mkstemp_function) (char *) = mkstemp;
+                  int fd = mkstemp_function (templ);
+                  if (fd < 0)
+                    result |= 1;
+                  else
+                    {
+                      struct stat st;
+                      if (lseek (fd, large, SEEK_SET) != large)
+                        result |= 2;
+                      if (fstat (fd, &st) < 0)
+                        result |= 4;
+                      else if (st.st_mode & 0077)
+                        result |= 8;
+                      if (close (fd))
+                        result |= 16;
+                    }
+                }
+              return result;]])],
+          [gl_cv_func_working_mkstemp=yes],
+          [gl_cv_func_working_mkstemp=no],
+          [case "$host_os" in
+                            # Guess yes on glibc systems.
+             *-gnu* | gnu*) gl_cv_func_working_mkstemp="guessing yes" ;;
+                            # Guess yes on musl systems.
+             *-musl*)       gl_cv_func_working_mkstemp="guessing yes" ;;
+                            # Guess no on native Windows.
+             mingw*)        gl_cv_func_working_mkstemp="guessing no" ;;
+                            # If we don't know, obey --enable-cross-guesses.
+             *)             gl_cv_func_working_mkstemp="$gl_cross_guess_normal" ;;
+           esac
+          ])
+        rm -rf conftest.mkstemp
+      ])
+    case "$gl_cv_func_working_mkstemp" in
+      *yes) ;;
+      *)
+        REPLACE_MKSTEMP=1
+        ;;
+    esac
+  else
+    HAVE_MKSTEMP=0
+  fi
+])
+
+# Prerequisites of lib/mkstemp.c.
+AC_DEFUN([gl_PREREQ_MKSTEMP],
+[
+])